Re: Central locking
Of the things you mention, the central locking is the easiest to sort out: you can add a standard kit easily. Try to get a kit with both front lock motors having five wires (for the switches: that way the doors lock/unlock from either side). The kit should be about 15-20 quid by my estimate, based on what they cost here in NZ. Run the wiring under the carpet along the sides, hook the power feed to the brown wire somewhere behind the stereo as this is live at all times. Get some corrugated wire-loom tubing, and make some holes with scissors in the door pillar rectangular blanking plugs (yes, really, a scissor blade, twisted, will allow you to make and enlarge a hole to exactly the right size for the wire-loom tube to fit!) Make it so that the tubing is fixed to one rectangular plug, and passes freely through the other plug as the door opens/closes.
To fit a lock-motor, just drill some holes in the door framework near the lock, and mount the lock-motor at a slight angle (not vertical), because the lock lever swings through an arc.
Thumbnails attached show rectangular blanking plugs from door pillars (note round hole made with scissors!), and lock motor mounting (front door of 5-dr).
The kit comes with some right-angle-ended rods and clamp blocks. There has been no need for the clamp blocks on my Unos, because the lock lever has a spare hole. All you need to do is to bend the rod with some vise-grips (locking pliers, I think you call them Mole grips), thread it through the hole in the lever, and squeeze the rod completely back on itself so that it forms a tight hook - who cares about how you would remove it
Obviously you have to get the bend in just the right place (a few measurements first with a thumbnail, perhaps, or do it before you fix the lock-motor in place). But there is nothing to slip or break off, and with a new lock-motor it should be totally reliable (remember to spray the mechanism with white grease before putting the trim back on).
Electric windows - give some thought to fitting relays inside the door, and a direct power feed from the battery. That way, the switches don't have to carry the full motor current, and the windows should be much more reliable. A bit of work, but you don't want non-working electric windows at any time! If you don't want to be creative with the electrics, you're better off to stick with manual windows!
Bigger engines: FIAT Tipo motor (1.6) would be a good upgrade for a 70 model.
Facelift mods: my choice is to paint the bumpers with black 'bumper coating', then mask off the bottom of the bumpers and paint with body colour (no other primer required). Makes the Uno look heaps better IMHO, more modern and less 'basic'. Consider also painting the door mirror casings (leave the concertina-piece black, for some reason it reminds me of a Porsche 911). Paint the grille also with bumper coating, unless you like mesh etc. (I don't, personally
) Oh yeah, hang on, if it's Mk2 then the grille's already body-colour, which is good (our Unos over here are almost all Mk1s!) And yes, I think the Mk2 grille looks quite nice with mesh in it, though I'd spray the mesh black first!
Other than that, as Dave says you should just buy an Uno Turbo - the ultimate Uno, I think we can agree
Then do the above mods to that.
-Alex