If you are going to bolt it in ,trans access is no big deal ,if welding it in you better leave plenty of room!! I think the tubular one would match the frame better and looks seem to be a big part of the objective on these cars. Some of the mods on my truck will be strictly for looks and some strictly for safety.
My opinion on things like this are ,if you have to add ,make or buy a part you might as well make looks part of the process.If you have to replace or buy a part that you do not have and its already costing 50-70 bucks ,I have no problem throwing another 50-70 bucks at it to make it look good also.

I would also make sure when you bolt something to a tubular structure you use a metal ferrul in the hole as to not collapse the tubing any at all.Round tubing looses its structural integrity when it gets collapsed or dented.If you use a 1/2 inch bolt ,drill a hole big enuff for 1/2 id piece of metal to pass thru the hole to keep the tubing from deforming from the pressure of the clamping force of the bolt.Ideally you would weld that ferrul into the tubing to make a flat flush area to tighten the nut and washer down to ,rather than a round surface under the washer and bolt,they make a specific tubing spacer/washer deal just for nuts and bolts on tubing.