One of the chronic niggles that affects the ZF transaxle is that they have a tendency to drool oil out the back side, due to the fact that oil seeps past the threads on the numerous studs which hold the back plate to the back edge of the case. Normally the gearbox is just held together with conventional open nuts.
Recently a friend turned me on to stainless steel sealing acorn nuts, a highly specialized fastener made by an outfit called Zago. Here's a photo:
It's a simple, yet brilliant concept. A groove is machined in the face of the nut to accept a rubber O-ring. The nut can be tightened to the point where you get metal-to-metal contact, so you can be assured of having the proper torque. The O-ring acts as both a seal and a lockwasher. Additionally, acorn nuts add a fair bit of bling to the rear of the gearbox.
Their website shows a variety of sealing fasteners, along with a gee-whiz video that shows how the concept works:
seal screws, self sealing screws and self-sealing fasteners manufactured by Zago Co
I've been speaking with their sales rep, and the price quote I got was for $2.65 each with a min quantity of 100, or the price drops to $2.05 each if I buy 500 or more. (Plus shipping etc.)
I haven't counted yet, but I believe there are 18-19 studs on the back of a ZF, so I'd be planning on selling these in quantities of 20, unless my count reveals the need to use a few more. That would mean that the cost to outfit a ZF would be in the $50-60 range.
I've already got a half-dozen Pantera guys on board (in just an hour) from the POCA forum, so I think with a little PI forum and GT40 forum interest, it shouldn't be difficult to get over the 500 unit hump.
If you're interested, please send me an e-mail directly and let me know. I believe that the SS nuts come in a dull SS finish; I can polish them for you for a slight additional cost.
I plan to sell these things at my cost, and won't require a cash commitment up front. Just say you want some, I'll put your name on a list, order and pay for them, then arrange for individual shipment/payment once they arrive. Figure $4.95 for flat-rate shipping in the USA.
Again, please e-mail me at MikeLDrew@aol.com to express interest.
Cheers!