Nice looking ZHP! You may want to sell yours and buy the M3 seperately. The market is very hot for ZHP's right now. Finding the perfect trade candidate may be tough.
There was a 1 owner e36 M3 listed on ebay by a BMW dealer that ended last night, 5x,xxx miles. Silver coupe, with dove grey vaders, could probably be had for $17kish. Auction ended but not buyers. If you search completed listings, you'll see it.