All depends, you told yourself that you will not drive the buggy, if this is true, having a 'shelf queen' is very hard to eat, sell them and get some cash from it.
Selling it as a roller is very interesting, but since people seems crazed to switch to a 5-R setup, your Prospec needs to be quite cheaper since if anyone buys them should end as a spare parts car or for someone who need to pull their teeth (all two needs very different equipments, one needs a roller, the other needs a most complete kit).