The same kit is used for both single and dual ear versions, and sells for $575.00 USD. I’ll ship anywhere in the lower 48 states for a flat $35.00. International freight charges are $135.00 USD. I can accept payment via Paypal (firstname.lastname@example.org) from verified accounts only. A personal/business check or money order is also accepted. Checks will delay shipping until cleared. Paypal and money order payments are shipped immediately upon receipt.
The reinforcement package is primarily geared towards the ///M versions of the Z3, but with some options on choice, it is just as easily fitted to the Z3.
The biggest difference between the two applications is that on the Z3, the spare tire carrier takes up some of the space required to fit the dual ear differential cover from the E36 M3. The choice is to either remove the spare tire carrier and its mounting bracket from the body (the tire can be carried inside the trunk) and use the dual ear cover, or to forego the dual ear in favor of keeping the spare in its original location. If you do that, all the same trunkfloor pieces are utilized, but I recommend taking a second OE rearmost differential mounting bracket and sectioning it to fit over the original one. By *sandwiching* these two brackets, you’ll double the thickness and strength of the single ear version.
My 99 M Rdstr has the doubled up single ear version with approximately 65,000 miles since conversion (95,000 now) with probably >20,000 of those miles running different superchargers (approx. 350 to 450 BHP). My 01 M Rdstr has the dual ear reinforcement, with perhaps 20,000 miles since being upgraded. Currently the 01 has about 46,000 miles total.
If you have any questions about the reinforcement package or its installation, I will be happy to answer them for you.
Sports Cars Plus, LLC
Parrish, Florida 34219