I bought my car from Northern Ireland and had to get it back ti the Isle of Man and I went the Belfast-Stranraer, Heysham-Douglas routes. It is a good 3.5 hour drive fron Stranraer to Heysham but the roads are nice and M6 easy to find. I'm guessing Warrington would be another hour, tops so if you don't mind a 4.5 hour drive then Stranraer would be good.
And don't look at the trip over as just extra money. Look at it from the point of view as a few days break with an upgrade for your car and some nice driving in between. The English aren't used to ferries because they can drive most places, when you live on an island, a ferry trip just becomes part of the journey.
I used to take my Prelude to track days but the Wings West front bumper was too low for the ramps on the boat so I used to jack it up and wedge blocks of wood in the suspension just to get it on and off the boat, I thought it was all part of the fun, rather than a nuisance or necessary evil.