I have a 1994 chevy lumina van,6 cylinder ; there are 3 sparkplugs on the front side of the engine(which we already removed),but how do we get to the ones in the back with the carburator,ar filter and everything else that's in the way??

I found this at the link below...

ALLDATA -- Jim Grant's Tech Tips --94 Chevy Lumina APV, Changing Spark Plugs (http://www.alldata.com/techtips/Chevy/20010219b.html)

Jim Grant's Tech Tips

94 Chevy Lumina APV, Changing Spark Plugs
Q: A Popular Mechanics Car Tips item indicated that the engine in this model had to be tilted forward in order to change the three rear spark plugs. However, two other auto manuals simply say the air cleaner assembly must be removed. Either way, it looks like a bear but which method do you suggest? Jack

A: Remove the air cleaner, tilt the engine, unbolt and discard anything that is in the way. Bear to work on? That's putting it mildly! Servicing the engine on that vehicle like many other vans of its type is a bear. Make sure you're not in a hurry, be sure there are no kids or mother inlaws around, and keep a few Band-Aids handy. Why? Because you're going to need time to find the tools you will throw. The Band-Aids are to cut back on the blood flow. You certainly don't want your kids learning new vocabulary words to use in class. Last but not least, you definitely do not want your mother inlaw around harping on your wife for marrying such a loser. If I were you I'd hire it done. But if you insist on doing the job just remember, no pain no gain.