Gap between shower tray and wall tiles

[1pudding1]

I am retiling and fitting a new shower. The shower has brick walls on 3 sides. Im using the exisiting shower tray. One wall is not quite parallel to the shower tray, so that when i put the tiles I will use against the wall, it doesnt overhang the shower tray at the bottom and there is a 5mm or so gap between the tile and tray which goes down between the tray and wall.

Whats the best way to deal with this? The old tiles on the bottom row were tilted so they met the shower tray. I'd rather not do that as Im also fitting a shower door. Can I put a load of silicone sealant in there? Or is there a plastic type l-shape fitting I could use?

Hope Ive explained that ok?

Thanks for any help.

 

[1pudding1]

Also, I have 300*600mm ceramic tiles to put up. Ive read I should be using BAL powdered adhesive and grout. Exactly which of these products should I buy? Im tiling onto plastered brick walls.

Cheers.