This really depends on your mechanical skills, if you have a floor jack, some 2x4s you can cut short and put on the jack you can jack the engine up slightly to gain access to the mounts, and replace the rubber as needed.. It's not easy, and not ideal, but will work, just jack it from the bell housing and not the oil pan.. as per the pistons, you will want to check the simple things first, is the coil bad? are you getting spark? how old are the plugs, how many miles are on it, what is the code its throwing, if it has the old ignition pack vs coil on plug you may have bad ignition wires, could also be bad compression.. disconnect the ignition coil lead or the fuel pump relay and hook a compression tester to the cylinder in question and crank the engine to see what you're getting for compression.. could also be a failing ECM or bad ground.. there should be a wire running from the engine block to somewhere in the bay, that could cause ignition issues.. could also be a stuck valve.. theres a lot to chek..
so yes.. you can do all these tests yourself, but you need to have some mechanical skill.. new and old engines arent that complicated.. Suck, squeeze, bang, blow.. fuel, air, compression, exhaust.. its been the same for 100+ years..