can i take out the stock 2in blocks and put 5in blocks in there?

 

Yea but you will need longer U-bolts and plan on having a-lot of axle wrap... New springs would be a better choice.

 

goin cheap route for now, will it be safe to drive?

 

Wow... 5 inch blocks? I guess you could drive it, but it sure doesn't seem really stable. You should plan on a longer set of shocks, brake line extensions, etc. There really isn't a cheap route.

Once you do all of this work, what happens when the axle twists the leaf springs to the point of breaking? There go your new brake lines, shocks, and all sorts of other carnage that'll have to be replaced.

...that may not happen, but it sure could.

 

In the redneck four wheeling world, the general rule is stay under 6 inch blocks, but of course as small as possible is better.

There are a lot of 6 inch blocks out there, and as long as you don't plan to work or wheel TOO hard, you should be fine.

As Mr. Cow mentioned, lots of other stuff to consider too. Don't cheap out and have your brakes fail the first time it flexes.

 

It may sound cheaper by just adding longer or thicker blocks. I did it once and wished I hadn't. You've never seen axle wrap until you add a 5-6" block to your suspension. Have you ever grabbed a short piece of pipe and used it to help ratchet off a stuck nut or bolt? Same phyolosophy applies. Adds leverage. It caused me to loose my rear axle once out rompin' in the mud. That low-cost, homemade 5" block cost me new springs, U-bolts, brake lines and a drive shaft. I would advise against it. Save your pennies and make it right.