beat87rx7

i have a 87mazda rx7 with a beat body every things wrong with it but the engine only has 65000 on it so im going to buy a new body with a blown engine and have my engine put in the new car does it matter if i have someone change my engines if there not real experienced with the rotary engines. or is it pretty much the same for both kinds of engines. and how much should it cost around to have both engines pulled from both cars and have the one put back in. thanks jim