02 ford escape engine swap
 

I got a ford escape that got rear ended, so I got another one with a blown engine and was going to drop the subframe from the rear-ended car since it has all new transmission with steering components. My questions are: 1. It leaks oil would I be better off taking the engine out before dropping the subframe or after or can I change all the gaskets while still attached to transmission? 2. Should I replace all the seals including the timing chain cover seals and valve cover seals? 3. It has 180,000 miles on the engine, is there any known issues that I should take care of while it's out?
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