I know that most of the factory suspensions that I have ever dealt with have either too long or too short of a tierod and pushing the suspension past it's intended use range will only create problems and unfortunately they get worse the lower that you go. You can adapt the outer tierod end to use a heim, but you just need to address it properly.
You would be best off by using a 3/4" heim with 1/2" misalignment spacers (
www.hm-engineering.com) and securing it either like the pic or get a hold of the guys on here that make the heim adapters. (I think you should be able to find a thread about attaching heims to spindles in the suspension forums)
Good luck