when replacing the camshaft does the engin have to be removed from the enginebay as the lifters must be inserted from the bottom

info need plz

In the end, the best way to change the cam is to pull the engine [it's not that hard] & mount it on an engine stand.
Remove the rocker cover, the rockers & pushrods.
Next comes the fuel pump, the distributor, water pump & timing case.
To get the timing case off you will need to pull the oil pan.

Remove the cam drive & invert the engine.
NOW you can change the cam. Simple isn't it.

Reasemble with new gaskets & seals where necessary & re-install the engine
That should be about a days work.

everything you have listed has been done the cam is out and the lifters are in the sump. brought gaskets, cam lube, 2nd hand lifters and pushrods(old ones were bent and were making noises at 6000 rpm)

is there another way to put the new cam in

If you can figure a way to hold the lifters up while you re-insert the cam, then go for it, but short of roling the car onto its roof, the engine will need to come out & this will be a lot easier than any alternate scheme that i have heard of so far.

that was my brothers method when he replaced the clucth in his sunny

is it possible to get to the lifters if you remove the sump

Thats the ONLY way to get to the lifters.

but can you get the sump off with the motor still in the enginebay or is the crossmember in the way

it doesn't matter if you can get the sump off with the engine in the car or not, because even if you retrieve the cam followers from the sump, you'll never get them and the cam back in with the engine in the car anyway - unless you have 8 telescopic magnets and an octopus to help out!

I guess that you could build a special brace that supports the engine in the car, then raise the car on a hoist, remove the inner suspension pivots, drop the crossmember out & remove the sump.
Then get four of your mates under the car to hold up the lifters while you slip the cam back in. Once it's back in, you need only put it all back together again.

I think that you will find that engine removal will be easier. It's all there in your workshop manual.