Your Sportrak seems to be suffering from the same problem as mine did when I first bought it - retarded ignition timing. There are two vacuum advance units mounted on the HDE engine, which control ignition timing and sub-timing. To correctly set the ignition timing on these engines you need to disconnect the sub-timing (Advance unit mounted closest to the distributor body, which is the unit connected rearmost on the intake manifold) and plug its vacuum port. The car usually runs okay if timing is retarded, albeit a bit sluggish, but returns poor economy. If correctly timed the engine should go like a rocket and get respectable mileage as well. The clunk in the steering is common and only involves cleaning and lubricating the stops from what I have read previously in these forums. If you need the relevant section of the Sportrak manual to do the timing job, send me your email address and I will send it to you.
David Mc