I've got a question for you. I have a 1990 full-size Chevy Blazer with the 350 and the stock automatic transmission. A couple weeks ago I installed chrome valve covers and custom gauges on my truck. The next time I drove it, I noticed that the transmission was not locking up properly (it shifted through all 4 gears, but the torque converter seemed not to lock up). This would happen intermittently, and it would often unlock spontaneously. I brought it to a transmission shop, and they replaced the lock-up cylinder, with no improvement. I have since been told that I need a complete transmission rebuild. Now, I dont really know how the lock-up works, and I've been wondering if in fighting with parts around the throttle linkage while installing the gauges and valve covers I might have done something to cause this intermittent behavior. Is this possible, and is there anything I can check? Second, I've been told that I can pull a plug on the transmission to disable the lockup entirely so that it will not act so unpredictably. Other than the sure decrease in gas mileage, will I notice any decrease in performance by doing this? If you could give me some pointers, I'd appreciate it. P.S. Any idea what the maximum recommended RPM for that engine is? Thanks.