If you are bored, looking for a winter project and the ~ $1500 isn't going to ding the budget too bad go ahead and do it. It will be a great selling point for the right crowd, but then again it could be a major red flag for a casual Porsche shopper.
When I had my 986 up for sale a local fellow was looking for a "fun" car, when I showed him the receipts and tried to explain IMS and RMS issue his eyes glazed over (as would most non-technical types) and I could tell he kind of freaked out at the stack of paperwork I had amassed.
When another fellow who was well versed on what to look out for on 986's (I sold the car through this board to another member) had seen what work was done it was definitely a very major selling point.
If you are going to sell through Autotrader, CL, For Sale sign in the window, etc. I'd say it wouldn't matter. If you are going to try to move it through a Porsche based forum it will help immensely.
IMO either way you would probably make out OK; if you put it in and sell you'll be very educated when it comes time to do it in the 996, if you put it in and keep it you're covered for the future then.
