Ford Repair: Replacement engine, head gaskets, ford dealership

Question
I have a 1998 Ford E-250 Super with the 4.2 liter engine.  I began to lose all power and could not find out what the problem was (even after taking it to a Ford dealership).  Later, after investigating on the web, I found out that the 97-98 4.2 liter had  a thin gasket problem that caused coolant to seep into the pistons (Ford quiet recall).  This was the problem and now all valves are warped through this.  I do not want to put another 4.2 liter in or even rebuild it(auto transmission with O.D.).  Can I go with a larger engine that was also placed in this van without any problems.  If so, what would your recommendation be and exactly what would require converting.  If there are a lot of conversions required, can I bypass all eletronics and place an older 302/351, etc with appropriate transmission without any problems.

Thanks again,

Doyal Campbell

Answer
Hello and thanks for the question...I'll try to help.
 I hate to say this, but stick with what's in there. The cost of you having to get an engine (different size/model/year) would require you to replace ALL of the electronics, PCM, and Harnesses for the engine. The problem with replacing it with an older one is that it still will have to pass your State inspection as a 98 4.2L, not what you have in the vehicle.
 If you are going to spend ANY money, rebuild the engine that's in there. Send it to a machine shop, do a valve job, replace the head gaskets with the updated ones, and be happy.
Hope this helps,
Erik