jimf posted this on the other site a while back. looked like pretty good home made to me.
This is my version of subframe connectors made from 4x4 steel tubing http://s901.photobucket.com/albums/ac213/coolgar/cougar/subframe/
You made those,…that is some super custom fab work! How far do they extent into the floor supports?
I got the Maier ones…and so far the look great 
still don’t have the car together enough to drive.
I have pics here: http://www.facebook.com/media/set/?set=a.1052344943175.9281.1062321859&type=3&l=d7734543d2
I’m thinking of getting these: http://www.ebay.com/itm/250640605552?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
Michael
I really think you ought to look at what 1970FastCat (Mike) did on his car. I think that ECI Bob did something similar and may have pictures (he is GOOD at documentation!) As I recall the square tube is actually running directly in line with the sub frames, reinforcing them rather than creating a separate sub frame under the car. In terms of strength, I would think that the continuous weld attaching the length of the square tube (to the floor of the car) would be a serious factor. From an engineering standpoint, in my own humble experience, materials hardly ever fail, attachment points fail all f the time. In any event the ones like Mike and Bob have look less tacked on.