I am swapping a 95 16v sidekick into my 87 Samurai. 
I took the engine out of the donor and have it on a engine stand.
Plan to change the seals and water pump and distributor O rings.

Any advice on what brand of seal to buy?
Napa, CARQUEST, rock auto? FEL-Pro, TIMKEN?
Anyone have bad seal and have to do the job over?
How long do they last? miles/ time
Anyone change Valve seals without taking the head off?
Engine run good in the sidekick but smokes a bit when first started.

thanks