Material handling lift conversion

I was given this great lift by a friend of mine. It's an ECOA MYTI-LIFT, electro-hydraulic unit, running off of 120V, that will lift 1000lbs. The current lifting surface is 24" x 36". Next week I'll be converting this to a proper motorcycle lift.
(image shown is the 500lb version)

Here's a photo with overlay showing the structural design of my modification:

The back section (closest, in photo), will be removable, in order to remove and service the rear wheel. I'm also going to make a removable ramp that hooks on to the back section. The extensions will be covered in 14 or 16 gauge sheet metal and made of rectangular section mild tubing.

I need to address the front wheel clamping mechanism as well. I'm thinking of going with one of these two designs:
Or the Derek Weaver W-Vice (http://www.derekweaver.com/update/W-Vise_Motorcycle_Lift_Accessories_Product.aspx?id=41), for only $89:$89 is cheap considering the amount of time it would take to fabricate this by hand, plus the materials I'd have to buy.

I'm debating whether to weld the length extensions to the existing plate, or bolt these. The rest will be welded most definitely. Bolting the whole assembly to the existing plate leaves ability to fabricate in place, then remove to powder coat. Breaking strength of any bolt over a 1/4" is so ridiculously high that throwing 4 5/16-18 per side will give me way more than needed. I'll probably go with some Grade 8 1/2" just for overkill.