I eventually stopped feeling sorry for myself yesterday and got on with trying to come up with some answers! In the end I re-plumbed part of the fuel system into a "jerry" can and took 20 litres out of the van's tank. I've had the van on the road again today and it doesn't appear to be spilling fuel any more so I think that's an improvement although I'm not entirely happy driving around with a known fuel tank problem.
I managed to get the tracking done too although it took over an hour in the end as the local tyre place still weren't organised at the right time. Whilst I was getting that done, the brake and ABS warning lights came on. I suspect a faulty sensor but it is yet another thing to investigate. The van only has ABS on the rear axle anyway and all the brakes still seem to work (well, apart from the parking brake which has always been pretty useless!)
My new trailer is definitely not going to be ready this week as some vital components still haven't been delivered to the manufacturer. I'm not one for giving up but I have given serious thought to pulling out of this weekend's race and cutting my losses. I think it is more sensible to investigate a hired trailer tomorrow and attempt to make the best of it now I at least have a usable van. I've never been this unprepared for a race weekend before! It doesn't help that I'm having the busiest week at work that I've had for some time.
This weekend had better be worth all this effort...