defender poorly need discovery help

So ok I should have checked but drove through a very deep puddle in my 90 Sunday at local pay and play and drowned the engine. Not good. Just bought myself a commercial disco and wondering where to start modding it for off-road. The defender was already done for me so I'm also wondering how much work and time is involved. I'm not working to a bugit but I can't afford to do it all at once. Help would be appreciated thanks.

Why don't you just fix or replace the engine in your 90?

x2, in my eyes just putting the 90 to one side and starting throwing money at something else is the wrong option.

If you take the rocker cover off and have a look at the push rods you may find a couple are bent.
If its more serious maybe an engine transplant would be quicker, and then you have time to put bits together for rebuild of your original engine when you have time / money.

Took rocker off and 4 push rods bent. Replaced them and changed oil. Only just turns over. I'm no mechanic but turbo has loads of play and when running its just farthing and tapping. Been offered 1500 as it stands so was gonna do the disco as I fancy a project

£1500 doesn't sound too bad especially as it doesn't start now, and that money would go quite a way for the disco. A water proofed snorkel wading kit and plugs for a start.
Did you find out where the oil was coming from?