Haven't got my charts to hand, so I can't give you a complete routing, but here's a couple of thoughts on the last part, which I know pretty well.
I did the SVFR route for the first time last weekend. I'd planned it several times, but I don't go in that direction very often, and every time I'd planned it the weather had different ideas until last weekend - but I did finally get around to it.
The Heathrow boys are very friendly, and more than happy to help you out. Give them a call on 119.9, but don't be surprised if the only reply you get is "Contact me on 132.7" which is the Thames frequency.
Once you get past that hurdle, request SVFR via Ascot. Expect to be cleared either not above 1000' or not above 1500'. Make sure you really do route via Ascot - on one leg last weekend I tried to fly a direct route, which took me about a mile abeam Ascot, and the controller was quick to point it out to me.
Make sure you speak to Denham and find out what their prefered arrival method is from this direction. I've done almost all my flying out of White Waltham, but suddenly realised, when about a mile from the edge of the ATZ, that I didn't have a clue how to join from this direction and at such low level without barging into the circuit!
Remember you need 10km viz for SVFR unless you have an IMC rating or IR.
If you decide not to go that way, or you can't get clearance, then you can stay in quite tight to the zone. There's a gap between Heathrow and Farnborough/Blackbushe that you can use. There are three danger areas in that gap, you can get a DAAIS from Farnborough, and you'll most likely find they're only active to 1400'. The TMA base is 2500', so that gives you plenty of room to squeeze through. After that, give White Waltham a call and transit their overhead. Overhead joins are at 1500' QNH, so you can easilly fly over the top of that without getting in anyone's way - but make sure you stay to the west of the field, or you'll be in the Heathrow zone. Continue north, and talk to Wycombe to get traffic information - tell them you're going to pass to the east of their zone, and fly through the gap between the ATZ and the Heathrow CTA. There are some good visual references for this gap, but don't rely on your GPS - mine has the size of the ATZ marked incorrectly. After that, simply turn right and fly DCT.
If that sounds too complicated, then routing to the west, through the Odiham MATZ, is the easiest option. Given that you'll want to be available to answer questions from mother-in-law Rimmer, you might be best routing this way and cutting down on the R/T - save the complicated routing for when you're solo, or you pax is a pilot or experienced pax who knows when to stop talking. Maybe you could try that on the way back, after dropping her off?
Have fun, whichever way you decide to go!
FFF
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