how many miles will a 5.0 last??

bought it with 82999, conn. state cop owned it, bought it new in 90, drove for 4-5 years ish, racked up 80k of them, then became a state cop, put my car in his garage where it lived for 10 years. he took it out sometimes he siad and im thinking thats where the 2,999 miles came from. the first day it came out of the garage the guy had to jump it to get me to test drive it, next day i bought it and put 500 miles on it getting it home, with who knows how old oil in it and everything else. we glanced under the hood and all we saw was dust and an intake manifold, nothing spraying everywhere so we drove it home. next day changed the oil, it was nasty. had rad flushed,ect. im at 87,200ish i believe been changin around 3k.

it leaks some oil in my front seal,and my valve cover gaskets have the flange of my headers gunked in oil stuff, im thinking thats because of the sitting for 10 years part.

i originally said to myself screw it im gonna build one before i get to 150 ish hopefully so whatever, but now im gonna take care of this engine and build the rest of the car up and just get really nice gaskets in there, and have someone take it apart and look at everything, and have them bolt it back up with better gaskets and im gonna take care of it and see hoe long it goes.

87k is nothing but i start it up at 6.30 am to go to school in whatever weather and start driving and it doesnt miss a beat, never stalls chokes bitches or moans. i had problems with it dying but that was because of my idle air controller.

clutch grabs hard and wont let go.

it gets talkitive and stuff and things get loud or squaky, and my clutch will sometiems get an attitude with me and grab wierd, but the mroe i drive it it smoothes itself out and fixes itself. i cant see it dying anytime soon. and im 17 and i beat on it.