Seeking advice.

I would use something like a trailer jack rather than jack stands. You can dial it in perfectly to whatever ground you happen to be on and not locked into 1" increments. Something like this: http://www.northerntool.com/shop/tools/product_200631778_200631778

I'm in the process of reworking my own small trailer to cook on the ramp with my SouthernQ Limo. For the last five years the trailer's role has been strictly that of a moving van - it gets the gear to the comp where it is completely unloaded to set up camp. Now age and gravity are dictating a new strategy! I've been planning this move for over a year, carefully observing other folks' setups and talking to them about where problem areas are. Here are a couple things you might want to keep in mind:

1) Your gate floor may need to be reinforced. When they engineer (and hopefully test) gates, they are thinking about loading small vehicles with good sized inflated tires. These type of tires spread the load over a wide contact patch, and the vehicle is usually only on the gate for a short time. Parking a cooker for a couple days that is putting all its weight on a tiny hard caster is a much more stressful load. I have seen a couple cases where the gate floor decking failed and the casters punched through.

2) Your gate structure may not be strong enough. As mentioned above, gates are designed to handle a dynamic load for short periods, with much of the weight being borne by the lowered edge of the gate. Two fat guys and a big steel cooker plus fuel, meat, etc. can exceed the gate frames load capacity. I've seen one instance where the gate structure broke and a couple others where the gate was noticeably bent from overloads.

3) You probably want to use a beam under the gate. The most common configuration I've seen is to support the gate with adjustable jack stands that have a 4x4 or 4x6 wood beam stretched between them. The gate rests on the entire beam, spreading the load out. Some wrap the beam in carpet to protect the gate finish. Some use two beams if the gate span is large and the load extra heavy.

4) Building an extension deck may not be practical. It will be expensive, difficult to transport and cumbersome to deploy. If your existing trailer gate won't accommodate your needs, it's probably time to consider trading up to a porch trailer.

5) There's more to consider than just the cookers. If you are still prepping on the ground, cooking off the deck doesn't solve the mud problem or keep you from stepping up and down all weekend. If you want to stay off the ground as much as possible, you'll also have to install a prep counter and probably a sink too inside the trailer. Now that you're using the trailer as a work area, air conditioning, insulation and lighting become important. Of course this all increases your costs, and once again you have to ask yourself is it worth it or is it time to get a new trailer.

As someone who is now essentially a solo cook, I'm hoping to get a couple more years out of my existing cargo trailer by cooking off the deck. Ultimately, I plan to sell the rig on to a younger team and replace it with a new porch trailer. Hope this helps!

I would just piano hinge the extension platform to the ramp and support it on the beams. You could lag screw a pair of stabilizer jacks (http://www.adventurerv.net/camco-olympian-leveling-stabilizer-scissor-jacks-57401-p-13854.html) to each of a couple of 4x4's and screw the base of the jacks to a decent length of 2x8 or 2x10 for stability. Just drop the gate down on the two beams, adjust height, and unfold the extension.

You probably want some bracket to hold the platform vertical so you can load and unload off the ramp and some kind of latch to lock it to the ramp when closed.

If this link works, you can see how we deal with cooking on the ramp of our cargo trailer:
https://www.facebook.com/yesdearbbq....1461940122./1032254013472680/?type=3&theater

We've since upgraded the jack stands to these: [ame="http://www.amazon.com/Camco-44531-Adjustable-Stabilizer/dp/B0024ECHXI/ref=sr_1_9?ie=UTF8&qid=1461940193&sr=8-9&keywords=camco+stabilizer+jack"]Amazon.com: Camco 44531 Adjustable Stabilizer: Automotive@@AMEPARAM@@http://ecx.images-amazon.com/images/I/31IsKQqtDOL.@@AMEPARAM@@31IsKQqtDOL[/ame] but the problem is that they're a little short so we have some blocks that raise them up.

I saw a really cool setup where the guy had built an aluminum beam and mounted 2 scissor jacks to it, and then he could position the beam wherever he wanted, and remove the whole assembly when he was done.

Safety, not for holding the weight, but for opening and closing the ramp, would be of major concern.

The trailer ramps have spring loaded cable assists on either side of the door and modifications would be required to use a side platform. Do yourself a favor, try lifting the ramp without the assists and then add several hundred pounds to said ramp and try lifting it. Without major assistance, it would be liable to crush someone, not to mention the need of a weight lifting belt to prevent hernias. This could be considered a dead-lift with no further explanations needed.

The use of several small sheets of aluminum diamond plates under the smokers on the ground and another one to use as a moving path when moving the smokers from the trailer might offer some relief. In addition, the use of an electric boat winch using a “D” ring anchor at the front of the trailer, when needed, makes easy work of moving up the ramp.

I use one to move my FEC100 and FE500 on and off my toy hauler without assistance and I’m north of 70.

Just saying, there are safer and simpler solutions for consideration.