Re: 87 70hp evinrude
Any 80s Evinrude/Johnson is a good engine if it has been cared for, in my opinion they are some of the best engines made.
I know you want to avoid any Ficht engine but I don't think the came out till after that.
If at all possible run it on a boat, short of that hear it run on muffs and if you can't do that at least do a compression check and a spark check. compression should be wihin 10% hot or cold and 100 or better is good.