Martin/MWCCWi, intrested in the welding trailer rigs? I found some of the old threads (went to the search and typed in "welding trailers")
here are some of them:
1) "Ideas I am building a welding trailer" by Snyder253 6-18-07
2) "Plans" by mark4561 3-28-07
3) "Welding trailer and flat bed trailer" by terry welds 3-26-07
4) New welder new project" by hit_em 3-19-07

this way, you can e-mail/post to those guys also for any more questions you may have....

hope this helps,