I have a welder - as long as he wants to sleep and eat here, he will do as I say.

Questions - Based on an anticipated TD weight of 1100 lbs:
1 - Should I buy a 4X8 and widen it, or buy a 5X8 and make it narrower? Either way seems fine to me, but there must be a pro/con.
2 - I'll be using a torsion axle - should the side rails be beefed up a bit?
3 - And last, but not least, and I'm sure this will get a war going (my apologies) - If you were to do this, what trailer would you buy and modify. I'm only asking as I suspect some of the trailers are better to work with in this regard than others due to whatever reason. I'd rather this NOT be a brand preference discussion if possible, but rather this to be an OBJECTIVE set of points.
Thanks in advance for your response! Everyone here has been giving me great advice so far!
Fred