Before I purchased my model II, I ordered the paper trail (history) from the FAA. There was one document in the packet, I believe from the second owner of the kit, stating there was no bill of sale passed to him from the original owner. Everything went through alright.
http://www.vansairforce.com/community/showthread.php?t=38916 The advice in this post parallels my opinion. You may consider as a number of users here and go with a handheld unit with a fabricated "mount". ....Lou