After much experimenting over several months and trying Polyprops with/without ESR simulating resistors this is the best sounding set up I have found, for anyone wanting to keep the original boards/design. The Sonicap Gen 1 Polyprops are one of my favourites for HF applications and one of the few available in the exact value required as a single cap, but any good PP would do, avoid cheap ones like Solen for the Tweeter. The top three Alcap electrolytics are 100v versions. The 25uf in the Mid range is a Low Loss Item (important) and is for the MD500 mid range, if using the MF500 add an ordinary 5uf Alcap in parallel with this. I have both sets of drivers and found the earlier MF500 to be smoother and more refined in its presentation, the MD500 gives a more forward midrange and because of its rating will ultimately play louder. The 25uf was used as the correct 24uf is no longer available. This is now more complicated because I have been informed the 25uf is also no longer available, I must have purchased some of the last ones, so a parallel pair of LL will be needed to make up the correct 24uf or 30uf value depending on the type of Mid driver fitted.