I'm debating wether or not to rebuild my own motor, buy a long block or have it rebuilt. The compression ranges from 148 to 165 but it burns alot of oil and smokes alot through the breather on the valve cover. I replaced the rear main seals a few months ago and the main bearings were pretty chewd up. And no it won't idle. The motor number is 1254083 but from what I have found it could be a few different years. I am leaning towards rebuilding it myself on a budget and would appreciate any advice on cheap upgrades or problems with these motors that I should look for. It's in an old jeep cj6 so I'm looking for low end power but nothing too crazy because it's an old jeep that doesn't need to be fast. I'm in San Diego and could use advice on a good machine shop. The nonstock stuff on my motor is an aluminum dual plane intake, 350 cfm holley 2-barrel and headers. Thanks for any help.